Health is the biggest single issue that could affect the way people vote in the assembly election, a BBC Wales poll has suggested.

One third of the people questioned said it was their main concern in the run-up to polling day in May.

Just under a fifth put jobs at the top of their list, while 14% said immigration was their priority.

Despite the priority given to health, 29% of respondents mistakenly thought it was run by the UK government.

Nearly two-thirds (65%) knew the Welsh government was responsible for the NHS.

The economy (11%), education (10%), Europe (4%) and crime (2%) were the other priorities of voters.

These were the findings of BBC Wales' annual St David's Day poll, carried out by ICM.

Image copyrightSteve Pope

Laura McAllister, professor of governance at Liverpool University, said: "I think it's interesting that we've now seen a slight increase at least in understanding that the Welsh government makes the key critical decisions around health in Wales.

"I suspect that's actually as a result of some of the quite vitriolic attacks on the performance and the governance of the NHS in Wales that have come from the UK government.

"Also, there's been some policy differentials around junior doctors strikes that haven't happened in Wales because of a different approach.

"So I think that a majority of people understand the NHS is run by the Welsh government has increased is a good thing.

"But I think, on the other hand, there hasn't been any great rise in understanding that the Welsh government can do things differently."

On immigration, just under half of respondents (47%) thought the numbers moving from outside of the UK into Wales was too high, while 37% thought it was just about right and 8% thought it was too low.

Plans to give income tax powers to Wales were supported by just over half of those questioned (54%), with 42% saying only the UK government should have control.

On powers for the Welsh assembly, 43% said it should have more while 30% thought its current powers were sufficient.

Image copyrightRichard Croft/Geograph

At the other ends of the scale, 13% wanted to see the assembly abolished and Wales governed directly from Westminster, while 6% supported independence.

The survey had sobering news for police and crime commissioners (PCCs) due to be elected on the same day as AMs.

Nearly nine out of 10 people (89%) failed to name any of Wales' current PCCs - one in ten could name one commissioner, while only 1% could name two.

Colin Rogers, professor of police sciences at the University of South Wales, said: "The previous election was really dogged by the fact that there was no significant debate, there was no significant awareness-raising of the role of commissioners.

"I think that needs to be embraced now to make people aware of what exactly commissioners do now and what their function can be in the future."

The last PCC elections in November 2012 saw a voter turnout in Wales of just under 15%.

ICM interviewed a random sample of 1,000 adults across Wales by telephone from 16 to 22 February 2016.